A student sets up a loudspeaker connected to an audio system to play music. Which row in the table correctly describes the main energy change taking place inside the loudspeaker?
Input energyOutput energyAelectricalsoundBsoundelectricalCchemicalelectricalDelectricalthermal only \begin{array}{|c|c|c|} \hline & \text{Input energy} & \text{Output energy} \\ \hline \textbf{A} & \text{electrical} & \text{sound} \\ \hline \textbf{B} & \text{sound} & \text{electrical} \\ \hline \textbf{C} & \text{chemical} & \text{electrical} \\ \hline \textbf{D} & \text{electrical} & \text{thermal only} \\ \hline \end{array} ABCDInput energyelectricalsoundchemicalelectricalOutput energysoundelectricalelectricalthermal onlyRow A
Row B
Row C
Row D
533 exam-style questions on CIE IGCSE Physics 1.7 Energy, work and power, covering 1.7.1a Energy stores and energy transfers, 1.7.1b Conservation of energy, 1.7.1c Kinetic and gravitational potential energy, 1.7.2 Work done, 1.7.3 Energy resources, 1.7.3a Energy resources and electricity generation, 1.7.3b Nuclear fusion as an energy source, 1.7.3c Efficiency of energy transfer, and 1.7.4 Power. Each one has a worked solution and a mark scheme showing where the marks go.